 #include <stdio.h>
 #include <errno.h>
 #include <string.h>
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>

 #define SERVER_IP "127.0.0.1"
 #define SERVER_PORT 8889
 #define MSG_STR "Hello, Unix Network Program World!"

 int main(int argc, char **argv)
 {
 int conn_fd = -1;
 int rv = -1;
 char buf[1024];
 struct sockaddr_in serv_addr;

 conn_fd = socket(AF_INET, SOCK_STREAM, 0);
 if(conn_fd < 0)
 {
 printf("create socket failure: %s\n", strerror(errno));
 return -1;
 }

 memset(&serv_addr, 0, sizeof(serv_addr));
 serv_addr.sin_family = AF_INET;
 serv_addr.sin_port = htons(SERVER_PORT);
 inet_aton( SERVER_IP, &serv_addr.sin_addr );

 if( connect(conn_fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
 {
 printf("connect to server [%s:%d] failure: %s\n", SERVER_IP, SERVER_PORT, strerror(errno));
 return 0;
 }

 if( write(conn_fd, MSG_STR, strlen(MSG_STR)) < 0 )
 {
 printf("Write data to server [%s:%d] failure: %s\n", SERVER_IP, SERVER_PORT, strerror(errno));
 goto cleanup;
 }

 memset(buf, 0, sizeof(buf));
 rv = read(conn_fd, buf, sizeof(buf));
 if(rv < 0)
 {
 printf("Read data from server failure: %s\n", strerror(errno));
 goto cleanup;
 }
 else if( 0 == rv )
 {
 printf("Client connect to server get disconnected\n");
 goto cleanup;
 }
 printf("Read %d bytes data from server: '%s'\n", rv, buf);


 cleanup:
 close(conn_fd);
 }
